In order to form furrows in fields of land, use is generally made of an elongate roller which is moved across the field. Such a tool is sometimes referred to in the art as a “furrow press”. The roller comprises an elongate cylindrical support and several tires mounted next to one another on the support, each tire operating in a respective furrow.
Each tire conventionally comprises a sole-forming part via which the tire is mounted on the cylindrical support, a tread-forming part via which the tire is in contact with the bottom of the furrow and two sidewall-forming parts each connecting the tread to the sole.
French patent application 15 52687 filed on Mar. 30, 2015 in the name of the Applicant Company describes a furrow-opening tire. The tread extends over a reduced portion of the width of the tire, at the radial end thereof. The side walls are formed as extensions of the tread. They connect to the sole. The sidewalls have an inclination that varies little and substantially continuously from the tread to the sole. These tires have a radial cross section in the overall shape of an equilateral triangle. The apex of this triangle corresponding to the radial end of this tire is rounded. These tires are able to work the ground effectively. They have good self-cleaning capability. Furthermore, the tires are effective at holding themselves against one another over time.
These tires make it possible to form furrows that are very close together. In other words, the strip of land between two adjacent furrows is narrow. The depth to which the tread penetrates the earth is very much dependent on the properties of this earth, such as its composition, its compactness and its wetness.
In order to create more widely-spaced furrows it is possible to interpose spacers between the tires. This impairs the self-cleaning capacity of the roller. Earth tends to build up on the spacers because of the rigidity thereof.
Furthermore, the spacers generally have an exterior surface of cylindrical shape. This means that the strip of land between two furrows becomes flattened.